Electrical discharges or arcs in the form of sparks and corona are present on virtually all electrical power distribution systems. Sparks can sometimes be seen as small bright flashes, while corona can sometimes be seen as a bluish glow around high voltage wires. They also create audible crackling or sizzling noise. Moreover, the discharges generate radio frequency (RF) noise that can be heard as static or buzzing on radio receivers, such as on HAM radio receivers.
Some sparks occur right on the primary and/or secondary conductors. These electrical discharges are herein called “primary arcs.” Other sparks occur on hardware located on the same structure as the conductor, but are not connected to the conductor. These other discharges are herein termed “induced voltage sparks.” These arcs are also known in the electrical power industry by various other terminologies. Primary arcs have high probability of leading to catastrophic equipment failure, whereas induced voltage sparks are primarily a concern for being a source of radio frequency (RF) interference while not necessarily being indicative of imminent equipment failure.
There are so many sparks on power lines and power poles that electric power utilities simply cannot fix all of them. In fact, most sparks are innocuous from a system reliability perspective. However, “primary arcs” usually carry current and are a warning sign of potential equipment failure. Being able to reliably and simply identify these discharges would permit a utility to better focus their repair efforts and more efficiently utilize available maintenance resources. Being able to distinguish from the RF or other noise detected by an RF receiver or other sensor whether the source is a primary arc or induced voltage sparks therefore is desirable.